The use of chordwise blowing over wing trailing edge flaps to increase their lift effectiveness, and spanwise blowing to sustain the vortex lift effect of leading edge vortices to higher angles of attack, are known in the prior art. Chordwise flap blowing is limited to aircraft having aft tails or canard surfaces which are needed to balance the nose-down moments associated with flap blowing. Spanwise blowing serves to raise the stall angle-of-attack limit, which is not helpful during landing when the aircraft pitch attitude is limited by tail-end clearance and the forward-view requirements of the pilot. Thus, there is a need in the art for a system to enhance the lift capability of low aspect ratio, highly swept wings of supersonic aircraft to thereby enable slower and safer landing on short runways or unprepared fields. The jet blowing of the present invention artificially creates vortex lift at the low angles of attack when the natural wing vortices are weak or absent, and at the same time, serves to generate a counter balancing nose-up moment to permit the use of trailing edge flaps; these two lift improvement effects then combine to improve the slow landing capability of tail-less swept wing aircraft.
It is therefore an object of the present invention to provide effective pneumatic lift augmentation for highly swept supersonic aircraft at low angles of attack during landing.
Another object of the present invention is to provide selective and controlled jet blowing over wing upper surfaces that enhances the lift capability of low aspect ratio, highly swept wings of supersonic aircraft to enable slower and safer landing on short runways.
A further object of the present invention is a jet blowing system for a highly swept wing supersonic aircraft that augments vortex lift at the low angles of attack when the wing vortices normally are weak or absent.
An additional object of the present invention is a jet blowing system for a highly swept wing, tail-less, supersonic aircraft that generates a counter balancing, nose-up moment that permits the use of trailing edge flaps to thereby improve the slow landing capability of the aircraft.
Another object of the present invention is a jet blowing system for a highly swept wing, tail-less, supersonic aircraft with selective asymmetric or one-side wing blowing to generate rolling moments for augmented lateral control of the aircraft.
Another object of the present invention is a spanwise tangential jet blowing system for the upper surfaces of a highly swept wing, tail-less supersonic aircraft to thereby stimulate vortex formation and resulting suction augmentation to provide a source of additional lift for the aircraft.
Still another object of the present invention is a system for generating vortex lift centered forward of the aircraft center of gravity to thereby produce a nose-up pitching moment which can assist in rotation during take-off and also permit counter-balancing of trailing edge flaps for lift augmentation of tail-less aircraft during the slow landing phase of a flight.